Use stat_col storage for stat_cols_info[] array instead of name_desc.
As documented in 65624876f ("MINOR: stats: introduce a more expressive
stat definition method"), stat_col supersedes name_desc storage but
it remains backward compatible. Here we migrate to the new API to be
able to further extend stat_cols_info[] in following patches.
Further extend logic implemented in 65624876 ("MINOR: stats: introduce a
more expressive stat definition method") and 4e9e8418 ("MINOR: stats:
prepare stats-file support for values other than FN_COUNTER"): we don't
rely anymore on the presence of the capability to know if the metric is
generic or not. This is because it prevents us from setting a capability
on static statistics. Yet it could be useful to set the capability even
on static metrics, thus we add a dedicated .generic bit to tell haproxy
that the metric is generic and can be handled automatically by the API.
Also, ME_NEW_* helpers are not explicitly associated to generic metric
definition (as it was already the case before) to avoid ambiguities.
It may change in the future as we may need to use the new definition
method to define static metrics (without the generic bit set). But for
now it isn't the case as this need definition was implemented for generic
metrics support in the first place. If we want to define static metrics
using the API, we could add a new set of helpers for instance.
Create a new module stats-proxy. Move stats functions related to proxies
list looping in it. This allows to reduce stats source file dividing its
size by half.
Currently, only FN_COUNTER are dumped and preloaded via a stats-file.
Thus in several places we relied on the assumption that only FN_COUNTER
are valid in stats-file context.
New stats types will soon be implemented as they are also eligilible to
statistics reloading on process startup. Thus, prepare stats-file
functions to remove any FN_COUNTER restriction.
As one of this change, generate_stat_tree() now uses stcol_is_generic()
for stats name tree indexing before stats-file parsing.
Also related to stats-file parsing, individual counter preloading step
as been extracted from line parsing in a dedicated new function
load_ctr(). This will allow to extend it to support multiple mechanism
of counter preloading depending on the stats type.
This commit is the first one of a serie to implement preloading of
haproxy counters via stats-file parsing.
This patch defines a basic apply_stats_file() function. It implements
reading line by line of a stats-file without any parsing for the moment.
It is called automatically on process startup via init().
Prepare stats function to handle a new format labelled "stats-file". Its
purpose is to generate a statistics dump with a format closed from the
CSV output. Such output will be then used to preload haproxy internal
counters on process startup.
stats-file output differs from a standard CSV on several points. First,
only an excerpt of all statistics is outputted. All values that does not
make sense to preload are excluded. For the moment, stats-file only list
stats fully defined via "struct stat_col" method. Contrary to a CSV, sll
columns of a stats-file will be filled. As such, empty field value is
used to mark stats which should not be outputted.
Some adaptation specifics to stats-file are necessary into
me_generate_field(). First, stats-file will output separatedly values
from frontend and backend sides with their own respective set of
columns. As such, an empty field value is returned if stat is not
defined for either frontend/listener, or backend/server when outputting
the other side. Also, as stats-file does not support empty column,
stcol_hide() is not used for it.
A minor adjustement was necessary for stats_fill_fe_line() to pass
context flags. This is necessary to detect stat output format. All other
listener/server/backend corresponding functions already have it.
This commit is a direct follow-up of the previous one which define a new
type "struct stat_col" to fully define a statistic entry.
Define a new function metric_generate(). For metrics statistics, it is
able to automatically calculate a stat value field for "offsets" from
"struct stat_col". Use it in stats_fill_*_stats() functions. Maintain a
fallback to previously used switch-case for old-style statistics.
This commit does not introduce functional change as currently no
statistic is defined as "struct stat_col". This will be the subject of a
future commit.
Previously, statistics were simply defined as a list of name_desc, as
for example "stat_cols_px" for proxy stats. No notion of type was fixed
for each stat definition. This correspondance was done individually
inside stats_fill_*_line() functions. This renders the process to
define new statistics tedious.
Implement a more expressive stat definition method via a new API. A new
type "struct stat_col" for stat column to replace name_desc usage is
defined. It contains a field to store the stat nature and format. A
<cap> field is also defined to be able to define a proxy stat only for
certain type of objects.
This new type is also further extended to include counter offsets. This
allows to define a method to automatically generate a stat value field
from a "struct stat_col". This will be the subject of a future commit.
New type "struct stat_col" is fully compatible full name_desc. This
allows to gradually convert stats definition. The focus will be first
for proxies counters to implement statistics preservation on reload.
The name "metrics" was chosen to represent the various list of haproxy
exposed statistics. However, it is deemed as ambiguous as some stats are
indeed metric in the true sense, but some are not, as highlighted by
various "enum field_origin" values.
Replace it by the new name "stat_cols" for statistic columns. Along with
the already existing notion of stat lines it should better reflect its
purpose.
Several unique names were used for different purposes under statistics
implementation. This caused the code to be difficult to understand.
* stat/stats name is removed when a more specific name could be used
* restrict field usage to purely refer to <struct field> which
represents a raw stat value.
* use "line" naming to represent an array of <struct field>
Info are used to expose haproxy global metrics. It is similar to proxy
statistics and any other module. As such, rename info indexes using
SI_I_INF_* prefix. Also info variable is renamed stat_line_info.
Thanks to this, naming is now consistent between info and other
statistics. It will help to integrate it as a "global" statistics
module.
Statistics were extended with the introduction of stats module. This
mechanism allows to expose various metrics for several haproxy
components. As a consequence of this, some static variables were
transformed to dynamic ones to be able to regroup all statistics
definition.
Rename these variables with more explicit naming :
* stat_lines can be used to generate one line of statistics for any
module using struct field as value
* metrics and metrics_len are used to stored description of metrics
indexed by module
Note that info is not integrated in the statistics module mechanism.
However, it could be done in the future to better reflect its purpose.
This commit is the first one of a serie which adjust naming convention
for stats module. The objective is to remove ambiguity and better
reflect how stats are implemented, especially since the introduction of
stats module.
This patch renames elements related to proxies statistics. One of the
main change is to rename ST_F_* statistics indexes prefix with the new
name ST_I_PX_*. This remove the reference to field which represents
another concept in the stats module. In the same vein, global
stat_fields variable is renamed metrics_px.
Extract functions related to HTML stats webpage from stats.c into a new
module named stats-html. This allows to reduce stats.c to roughly half
of its original size.
Just like for the cache applet, it is now possible to send response to the
opposite side using the zero-copy forwarding. Internal functions were
slightly updated but there is nothing special to say. Except the requested
size during the nego stage is not exact.
The list of modules registered on the stats to expose extra counters is now
public. It is required to export these counters into the Prometheus
exporter.
stats_putchk() is updated to use the applet API instead of the channel API
to write data. To do so, the appctx is passed as parameter instead of the
channel. This way, the applet does not need to take care to request more
room it it fails to put data into the channel's buffer.
In ("BUG/MEDIUM: stats: Rely on a local trash buffer to dump the stats"),
we forgot to apply the patch in resolvers.c which provides the
stats_dump_resolvers() function that is involved when dumping with "resolvers"
domain.
As a consequence, resolvers dump was broken because stats_dump_one_line(),
which is used in stats_dump_resolv_to_buffer(), implicitely uses trash_chunk
from stats.c to prepare the dump, and stats_putchk() is then called with
global trash (currently empty) as output data.
Given that trash_dump variable is static and thus only available within stats.c
we change stats_putchk() function prototype so that the function does not take
the output buffer as an argument. Instead, stats_putchk() will implicitly use
the local trash_dump variable declared in stats.c.
It will also prevent further mixups between stats_dump_* functions and
stats_putchk().
This needs to be backported with ("BUG/MEDIUM: stats: Rely on a local trash
buffer to dump the stats")
If we add a new stats module to C source files including only
stats.h we get these errors:
include/haproxy/stats.h:39:31: error: array type has incomplete element type
‘struct name_desc’
39 | extern const struct name_desc stat_fields[];
include/haproxy/stats.h:55:50: warning: ‘struct listener’ declared inside
parameter list will not be visible outside of this definition or declaration
55 | int stats_fill_li_stats(struct proxy *px, struct listener *l, int flags,
name_desc struct is defined in tools-t.h and listener struct in listner-t.h.
channel, stream_interface, appctx, buffer, proxy and htx ones are used
in function arguments and most of them are not defined but were inherited
from intermediary inclues. Let's define them here and drop the unneeded
includes.
Currently the stats filling function knows nothing about the caller's
needs, so let's pass the STAT_* flags so that it can adapt to the
requester's constraints.
Remove static qualifier on stats_allocate_proxy_counters_internal. This
function will be used to allocate extra counters at runtime for dynamic
servers.
prometheus approach requires to output all values for a given metric
name; meaning we iterate through all metrics, and then iterate in the
inner loop on all objects for this metric.
In order to allow more code reuse, adapt the stats API to be able to
select one field or fill them all otherwise.
From this patch it should be possible to add support for listen stats in
prometheus.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
prometheus approach requires to output all values for a given metric
name; meaning we iterate through all metrics, and then iterate in the
inner loop on all objects for this metric.
In order to allow more code reuse, adapt the stats API to be able to
select one field or fill them all otherwise.
This patch follows what has already been done on frontend and backend
side.
From this patch it should be possible to remove most of the duplicate
code on prometheuse side for the server.
A few things to note though:
- state require prior calculation, so I moved that to a sort of helper
`stats_fill_be_stats_computestate`.
- all ST_F*TIME fields requires some minor compute, so I moved it at te
beginning of the function under a condition.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
prometheus approach requires to output all values for a given metric
name; meaning we iterate through all metrics, and then iterate in the
inner loop on all objects for this metric.
In order to allow more code reuse, adapt the stats API to be able to
select one field or fill them all otherwise.
This patch follows what has already been done on frontend side.
From this patch it should be possible to remove most of the duplicate
code on prometheuse side for the backend
A few things to note though:
- status and uweight field requires prior compute, so I moved that to a
sort of helper `stats_fill_be_stats_computesrv`.
- all ST_F*TIME fields requires some minor compute, so I moved it at te
beginning of the function under a condition.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
while working on backend/servers I realised I could have written that in
a better way and avoid one extra break. This is slightly improving
readiness.
also while being here, fix function declaration which was not 100%
accurate.
this patch does not change the behaviour of the code.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
use `stats_fill_fe_stats` when possible to avoid duplicating code; make
use of field selector to get the needed field only.
this should not introduce any difference of output.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
prometheus approach requires to output all values for a given metric
name; meaning we iterate through all metrics, and then iterate in the
inner loop on all objects for this metric.
In order to allow more code reuse, adapt the stats API to be able to
select one field or fill them all otherwise.
From this patch it should be possible to remove most of the duplicate
code on prometheuse side for the frontend.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
This is executed on startup with the registered statistics module. The
existing statistics have been merged in a list containing all
statistics for each domain. This is useful to print all available
statistics in a generic way.
Allocate extra counters for all proxies/servers/listeners instances.
These counters are allocated with the counters from the stats modules
registered on startup.
A stat module can be registered to quickly add new statistics on
haproxy. It must be attached to one of the available stats domain. The
register must be done using INITCALL on STG_REGISTER.
The stat module has a name which should be unique for each new module in
a domain. It also contains a statistics list with their name/desc and a
pointer to a function used to fill the stats from the module counters.
The module also provides the initial counters values used on
automatically allocated counters. The offset for these counters
are stored in the module structure.
This flag can be used to determine on what type of proxy object the
statistics should be relevant. It will be useful when adding dynamic
statistics. Currently, this flag is not used.
Render the stats size parametric in csv/json dump functions. This is
needed for the future patch which provides dynamic stats. For now the
static value ST_F_TOTAL_FIELDS is provided.
Remove unused parameter px on stats_dump_one_line.
This patch is needed to extend stat support to components other than
proxies objects.
Un-mark stats_dump_one_line and stats_putchk as static and export them
in the header file. These functions will be reusable by other components to
print their statistics.
This patch is needed to extend stat support to components other than
proxies objects.
This patch fixes all the leftovers from the include cleanup campaign. There
were not that many (~400 entries in ~150 files) but it was definitely worth
doing it as it revealed a few duplicates.
Just some minor reordering, and the usual cleanup of call places for
those which didn't need it. We don't include the whole tools.h into
stats-t anymore but just tools-t.h.